Blowing device



Sept: 18, 1928. 1,684,752

R. H. WILHELM BLOWING DEVICE Filed Jan. 29, 1927 1175541 ORNEY Patented Sept. 18, 1928.

UNITED STATES.

PATENT OFFICE.

RUSSELL H. WILHELM, 0E EASTON, P NNSYLVANIA; rissrenon T0 rneEnsoLL-mmn COMPANY, OF JERSEY CITY, NEW JERSEY, A oonro'nnrron' or NEW JERSEY.

BLOWING DEVICE.

Application filed January 29, 1927. Serial No. 164,478.'

This invention relates to rock drills, but more particularly to a. blowing device for fluid actuated rock drills of the hammer type.

The objects of the invention are to permit an uninterrupted supply of pressure fluid under full line pressure to flow through the device and the drill steel for'removing the cuttings from the drill hole and to prevent reciprocation of the distributing valve and the'piston during the blowing period. I Other objects will appear hereinafter.

The invention is shown in one of its preferred forms in the accompanying. drawings, in which Figure 1 is a longitudinal sectional elevation of a rock drill showing the relative position of the moving parts when the piston is on its forward stroke; a

Figure 2 is a view similar to that in Figure 1, showing the relative position of the moving parts when the piston is on its rearward stroke, and I Figure 3 is a view similar to Figures 1 and 2, showing the valve held inoperative in the valve chamber.

Referring to the drawings, a cylinder A of the rock drill is provided with a back head P, a front head G and a piston D. The piston D has a reduced striking end consisting of a. smooth cylindrical portion D and a fluted shank O.

During the operation of the tool the piston D delivers blows of impact to a drill steel K which is secured in its operative position by a chuck H which engages the shank J of the drill steel K. The interior surface of the chuck H is fluted as at L to cooperate with the fluted end O of the piston D. A front cylinder washer E forms a closure for the front end of the cylinder A and acts as a guide to centralize the piston D.

Automatic rotation of the drill steel is provided by the usual rifle bar Q, extending for- I wardly from a rotation washer Q, located in aback head P, back head P forming a closure for the rear end of the cylinder A.

A valve chest S, mounted on the cylinder A- and preferably formed integral therewith, is provided with a longitudinal bore T of uniform diameter throughout its length. A piston valve U having end heads iv and V and a central head X is reciprocably mounted in tne bore T- Plugs Y and Z form closures for the rear and front ends respectively of the valve bore T and maybe held in place in any suitable manner.

- In addition to forming a closure for the froFnt end of the valve bore T the plug Zhas a iorwardly extending portion (Z which is provided with a slot o at its forward end and aboige c centrally located and extending longituoinally pf the plug. The bore edoes not extend tne rull length of the plug, but connects with smaller bore thus forming a shoulder '11). v

Motive fluid 1s supplied to the drill at an lnletaurrom a source of supply (not. shown).

Motive fluid enters the cylinder A thru a passage 5 and the piston D is driven forward.

At the same time spent motive fluid is 621-.

hansted from the front. end of the cylinder thru a passage C and to the atmosphere by way of a suitable eXhaust post 50. hen the advancing piston has uncovered a passage Z) live pressure fluid is delivered to the face of the valve X and the valve is thrown rearwardly admitting pressure fluid to the passage C and thus driving the piston rearwardly. When the returning piston uncovers a passage 0 the valve X is again thrown forwardly and live pressure fluid admitted to the rear end of the cylinder. This cycle of operations is continued indefinitely at the will of the operator.

It frequently becomes necessary during the operation ofdrilling a hole to blow the hole free of rock chips and dust. To facilitate this blowing or cl'eai'iing operation the invention now to be described was devised.

. When blowing the rock cuttings and dust from the drilled hole it is necessary to hold thedistributing valve X in its rearwardmost position to allow a free passage for the motive fluid from the inlet a thru the passa e G into the cylinder A thru the flutes 0 add into the passage 4) of the drill steel K.

To thrust and hold the valve X into the required position a lever 7' having a handle .9 and a cam portion 25 is rotably mounted on a pin 9 in the slot 9. A plunger uextending into the bore 6 is held in contact'with the cam The rearward end of the r t by a spring 0. spring 0 seats against a piston or plunger head h 111 the bore e. The plunger head h has a reduced, rearwardly extending por tion 9 Which'fits slidably the bore 7'. 1nterposed b wegmherenewing the plun er head hand the shoulder w, surrounding t 1e plunger 9, is a spring 10. 1 N rma l t P u r 9 ,i h d W f contactvvith the valve U but when ithecomes necessary to blow the drilled hole clear of dust and rock chips the operator pnlls the lever or handle 8 rearwardly. By the action of the cam -t the plunger u is forcedqinto the bore 6, the springo is compressed and it in turn compresses the spring I: behind the plunger head h. The plunger 9 being forced rearwardly contacts with the valve U andsecurely holds it in its rearward position permitting an uninterrupted supply of mo- (not shown).

tive fluid to flow from the inlet a into the valve chamber T, thru the passage Q, into the cylinder A, thru the flutes O and thru a bore v in the drill steel K into the drilled hole With the valve in the position last described the exhaustport w is covered in such a Way that the motive fluid can only escape by way of the bore o in the drill steel 70.

When the operator desires to stop the flow of pressurefluid to the drilled hole and resume the operation of drilling it is only necessary fo'rhim to push the lever s forwardly and the spring 70 will withdrawthe lunger 9 from the face of the valve U and the valve chamber to t torming closures for the ends of the c amspecification.

immediately begins its normal functioning.

I claim: 7 e n In a fluid actuated rdqli all t hammer type; the comhiliation of e lin er, tl hammer piston in the cylinder having a reduced forward ezgtension, a valve chest havin a chamber, suplgly passe esleiidifig lfie ends 2) the eyelids, lugs her, a plunger slidable in one of the plugs, a

holding the plun 'er out of contact with the valve, the second spring normally. in contact with said plunger,. means for'lectuating the plunger to hold the valve immovable in the valve chestto permit an uninterrupted "pan: ofcspringsyione of. said springs normally flow of pressure fluid from ai source of s p; 1

ply through the said chamber and a supply 7 passage and through one end ofthe cylinder to a holloiv drill steel, said means comprising a cam, a lever attached to said cam,ra pl,un'ger in contact with said cam, said second spring 1 a in contact with said secondw'plu'n er, said second spring holding said second p ,ungjer in contact with said cam,isaid cain .operableby means of said leverfor forcing saidfscond plunger into said phiand mechanically holdingsaid first saidvalve; v v i A In testimony whereof I have signed this plunger in contact wit messes 1 1; 

